Just wanted to type up a 'splainer for the tech side of some home music video production. Most of it is shown in the picture above, so really not a lot to it.
The signal starts at the microphones. The big one is a CAD Equitek E-200 from, I don't know, 15-20 years ago? The other one is an AKG C-1000S from at least 20 years ago.
The mics' XLR cables terminate at the little Mackie mixer, a 1202-VLZ. Again, ancient history.
The mixer outputs to an AVID Mbox Mini USB interface, which does the analog-to-digital conversion of a mix of the two microphones' signals. Mono or Stereo. My son gave me this box years ago and I wondered, what would I do with this? Now, I know.
The USB interface connects to a couple-years-old Chromebook. There, on the Linux side of its world, I have been running Audacity for audio data collection and mixing and Flowblade for the video editing.
The drill goes like this:
Spend an inordinate amount of time setting the gain levels between the mics and the mixer, and the mixer and the USB interface. If this isn't right, nothing else really matters and you can stop here.
Record audio tracks one (mono) or two (stereo) at a time into Audacity while simultaneously shooting video (and not-necessarily-high-quality-audio) from your cellphone or camera.
Pile up as many of these audio/video pairs as you want.
Using Audacity, mix the pile of mono or stereo audio tracks into a single stereo .WAV file.
Collect the video files from your cellphone or camera, probably .MP4 files.
Use Flowblade to produce the finished product by combining the various .MP4 video files with the .WAV audio file. (The coolest feature of Flowblade is that it can sync a video file from a phone to the .WAV file you created with Audacity. It somehow mathematically matches stuff up and it works really well.)
Render the final .MP4 video from Flowblade.